From: Martin Schwidefsky <schwidefsky@de.ibm.com>
Date: Tue, 24 Apr 2018 11:18:49 +0200
Subject: s390: remove indirect branch from do_softirq_own_stack
Git-commit: 9f18fff63cfd6f559daa1eaae60640372c65f84b
Patch-mainline: v4.17-rc6
References: git-fixes f19fbd5ed6
The inline assembly to call __do_softirq on the irq stack uses
an indirect branch. This can be replaced with a normal relative
branch.
Cc: stable@vger.kernel.org # 4.16
Fixes: f19fbd5ed6 ("s390: introduce execute-trampolines for branches")
Reviewed-by: Hendrik Brueckner <brueckner@linux.vnet.ibm.com>
Signed-off-by: Martin Schwidefsky <schwidefsky@de.ibm.com>
Acked-by: Petr Tesarik <ptesarik@suse.com>
---
arch/s390/kernel/irq.c | 5 ++---
1 file changed, 2 insertions(+), 3 deletions(-)
diff --git a/arch/s390/kernel/irq.c b/arch/s390/kernel/irq.c
index 94f2099bceb0..3d17c41074ca 100644
--- a/arch/s390/kernel/irq.c
+++ b/arch/s390/kernel/irq.c
@@ -176,10 +176,9 @@ void do_softirq_own_stack(void)
new -= STACK_FRAME_OVERHEAD;
((struct stack_frame *) new)->back_chain = old;
asm volatile(" la 15,0(%0)\n"
- " basr 14,%2\n"
+ " brasl 14,__do_softirq\n"
" la 15,0(%1)\n"
- : : "a" (new), "a" (old),
- "a" (__do_softirq)
+ : : "a" (new), "a" (old)
: "0", "1", "2", "3", "4", "5", "14",
"cc", "memory" );
} else {